Method of and mechanism for tapping articles



Oct. 18, 1932. J. F. PATTON 8 METHOD OF AND MECHANISM FOR TAPPING ARTICLES Filed June 27. 1927 7 Sheets-Sheet l 3 mm mm 0N JNVENTOR. Jar/ms Ffiz ffon ATTORNEYS Oct. 18, 1932.. i I J PAT-TON 1,882,874

METHOD OF AND MECHANISM FOR TIrPPING ARTICLES Filed June 27. 1927 7 Sheets-Sheet 2 INVENTOR.

James P417272 BY M a 904.4

A TTORNEKS Oct. 18, 1932. J, QN 1,882,874

METHOD OF AND MECHANISM FOR TAPPING ARTICLES Filed June 27, 1927 '7 Sheets-Sheet 3 1 N VEN TOR.

c/zmesF/Zz/fon A TTORNE -S Oct. 18, 1932. J PATTQN 1,882,874

METHOD OF AND MECHANISM FOR TAPPING ARTICLES Filed Jgne 27, 1927 7 Sheets-Sheet 4 IN VEN TOR.

(ft/ma," Flax/J5 BY 30: .M t @904 A TTORNEY-S Oct. 18, 1932. J. F. PATTON IETHOD OF AND MECHANISM FQR TA PP ING ARTICLES 7 Sheets-Sheet 6 Filed June 27 1927 INVEN TOR. def/ms FI af/OZ 0&2- 5

Oct; 18,1 19.32. J. F. PATTON 1,882,874

METHOD AND MECHANISM FOR TAPPING ARTICLES Filed June 27, 1927 7 Sheets-Shee t 7 INVENTOR. Y James FPai/arz B 80 1r 9 A TTORNEKS Patented Oct. 18, 1932 UNITED STATES JAMES F. PATTON, or CLEVELAND, 01110 METHOD OF AND MECHANISM FOR TAPPING ARTICLES Application filed June 27,

This invention relates, as indicated, to metlioo and apparatus for tapping articles and refers more particularly to a new and improved tapping machine wherein blanks a are continuously fed to a suitable holder and are automatically operated upon in such positicn by the threading, device, each of the several operating elements of the machine being actuated automatically and continuie ously. I

My invention contemplates'the provision of an automatic machine of the present type having a horizontally or longitudinally arranged tapping tool, which tool is provided at one end with thread-cutting elements and has its other end constructed for the engagement of a detachable support. I am acquainted with the present well-known types of tapping machines, in which is employed an elongated tap having one end thereof provided with a bent portion which cooperates with a complementary curved recess in the supporting elements of the machine to prevent not only'rotation of the tap, but also longitudinal displacement thereof. In such types of machines the articles to be threaded are carried in a revolving head which moves axially of the threading tool, these articles after being threaded passing beyond the actual threading elements of the'tool and being carried along the shank thereof and discharged from its opposite end; Not only is the cost of these bent taps quite considerable,- but the use thereof necessitates thevnon-revolving of the tap. The present invention primarily permits either the rotation of the tap or of the articles, as well as permitting the use of a straight tap.

An object of this invention is to provide a novel work-carrying head which is adapted to grip in alignment two or more articles to be threaded and to so design the operating mechanisms of the machine that the tap will be actuated in its longitudinal movement through its threading engagement with the article held in such head nearest the tap.

A further object of the invention is to provide in such work-carrying head suitable work-gripping means which are intermittently actuated by each cycle in the op- 1927. Serial No. 201,648.

eration of the machine. In its simplest form the invention comprises the provision of a work-carrier having a pair of gripping jaws adapted to hold two articles in parallel spaced alignment and mechanism which discharges one of such articles from the carrier and at the same time positions the other article in the place of the discharged one. Such mechanism is also adapted to simultaneously insert a fresh article in the position of the second article. At the starting point in the article at the start of the operation. Thereafter the tap is retracted to starting position, carrying with it the article engaged by its threading elements and the machine is ready to start another cycle in its operation.

A further object of the invention is to provide mechanism for engaging the free end of a tap during the threading operation of the machine. This mechanism may be so designed that in the case where the work holder is revolved the tap will be held stationary during threading operation, or, if the work holder is held from rotation suitable 8'5 driving devices may be provided cooperating with such tap engaging mechanism for revolving the same. My invention also contemplates the provision of a stripping device which is engaged about the end of the tap adjacent the free end thereof and such mechanism is designed to cooperate with the tap holding mechanism so that when the latter is disengaged from the end of the tap such stripper will automatically discharge threaded articles which have traversed the tap shank from the threading position.

A still further object of the invention is to provide in connection with a hopper, an automatically operated shank feeding mechanism which is actuated simultaneously with the release of the gripping mechanisms carried in the carrier head to feed blanks from such hopper to the carrier head.

Another object hereof is to provide a tapping machine of the present improved character wherein each of the several operating elements are actuated continuously and in timed relation with each other and to provide adjustments in said several. operating elements to adapt the machine for awide range of usage. 7 r e To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the annexed drawings and the following description setting forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention maybe used.

In said annexed drawings Fig. l is a front elevational View of a preferred embodiment of my invention;

Fig. 2 is a rear elevational View of the same;

Fig. 3 is a longitudinal central sectional view taken on the line 3-3 of Fig. 2;

Fig. l is a transverse vertical sectional view on an enlarged scale of the work chuck or carrier as taken on line 4-4 of Fig. 2;

Fig. 5 is a longitudinal vertical sectional view of the same taken on line 5-5 of Fig. 1;

Fig. 6 is a transverse vertical sectional view.

taken on line 66 of Figs. 1 and 2 in the direction of the arrows;

Fig. 7 is a longitudinal vertical section taken on line 77 of Fig. 6;

Fig. 8 is a fragmentary detail view of certain of the elements illustrated in Fig. 7 showing the same in a different operative condition r V Fig. 9 is a detail view of the drum operating latch;

Fig. 10 is a transverse vertical sectional view taken on line 10-1O of Fig. 1;

Fig. 11 is a similar view taken on line 1111 of Fig. 1; and

Figs. 12 to 15, inclusive, are diagrammatic views illustrating in sequence the essential steps in the operation of one complete cycle of the present machine.

I have illustrated in the accompanying drawings a preferred embodiment of this invention which comprises a bed plate 1 mounted on a suitable support or legs 2 and having a number of vertical standards or pro jections carried on its upper surface. Certain of these standards, designated in the drawings by numerals 3 and 4, are adapted to provide longitudinal supports for the revolving spindle, the blank feeding mechanism, the cam drum and other operating elements, as will appear more fully hereinafter, and may I ried at the other end of the spindle.

The work-carrying mechanism Referring now to Fig. 3 the spindle 8 is shown in the form of a hollow or tubular shaft provided at its forward end with an enlarged portion 11, to which the spindle shank 12 of the work-carrying head may be secured by screw threads 13. The inner diameter 14 of the spindle 8 is sufficient to permit the articles worked upon to freely pass therethrough. In this figure is also seen the relative position of the worm wheel 7 and the tapping tool 15, which latter member is to be described more fully hereinafter.

Proceeding now to a more detailed description of the work carrier, the spindle shank 12 referred to above is formed at the rear end of the head proper and is provided with a central bore 16 of equal diameter to the interior 14 of the spindle 8. In Figs. 4 and 5 the work-carrying head 9 consists of an annular body member. carrying in its interior certain work-gripping mechanisms which, as

has been previously stated, are actuated automatically to grip two or more articles in alignment. This gripping mechanism consists of a relatively fixed or block 17 received in an annular recess 18 provided at the center ofthe head 9 and having formed at its inner periphery a plurality of serrations 19; Cooperating with the fixed jaw 17 is one or more movable jaw members 20, these latter jaws being carried in recesses 21 formed transversely of the head 9. Recesses 21 may be formed in any desired manner in the work-carrying head and are extended clear through such head to provide for the reciprocation of the jaws 20. Serrations 22 are provided on aws upon an inclined surface 23 formed on the side thereof adjacent the center of the head 9. A com pression spring 24 is positioned in recess 25 formed in one end of each jaw to lie between such member and the exterior of an annular ing 26 secured to the outer periphery of the work carrying head 9. The function of these springs obviously tends to normally force the jaws 2O inwardly toward the fixed jaws 17 and thus engage the work, herein shown as annular coupling members 27. The other ends of the reciprocating aws 20 are received.

in a reduced portion 28 of the recess 21 and are provided with inclined or cam surfaces path of an actuating cam with a plurality of inclined or cam surfaces 34! which cooperate with the cam surfaces 29 on the movable jaws to actuate the latter upon movement of such slide. The rear end of the cam slide 30 is projected beyond the exterior oft-he head 9 and is secured by a nut 36 to a grooved collar 37. This collar 37 as best seen in Fig. 5 is slidably mounted on the head spindle 12 and is engaged by shoes 38, which ride in the groove 39 of the collar. Pivotally mounted upon the bed of the machine about a stud 10 is an encircling yoke iember 41, in the sides of which are secured pins 42 by which the shoes 38 are carried. At the upper end ofthe yoke 11 is secured a cam project-ion 43, which is adapted to be engaged by suitable mechanism to be presently described to rock the yoke about its pivot and consequently move the cam slide 30 relatively of the work head 9. It will be apparent from the foregoing that the couplings 27 are normally gripped between the jaws 17 and 20 and that upon actuation of the yoke ll the jaws 20 will be moved against the springs 2a, and thus free the couplings.

A feature in the construction of the workgripping jaws consists in the particular shape of the serrations 19 and 22. \Vhile the jaw 17 has been referred to as fixed, this member is received in the recess 18 in the head and confined therein by the end plate 33 and is permitted of a slight oscillatory movement. The serrations 22 as seen in Fig. l are so formed that when engaged with the blanks 27 they tend to draw the jaws 20 inwardly of the head to more tightly en age with such blanks. In the operation of the machine it will of course be understood that the blanks 27 are acted upon by the threading tool or tap 15, and on account of such threading operation the blanks will tend to rotate within the head 9. This rotary tendency of the blanks causes the jaws 20 to be drawn into more firm engagement therewith on account of the construction of the serrations 22 as described, the jaw 17 permitting the slight oscillatory movement referred to to eliminate the disfigurement of the exterior of the work. As the jaws 20 are drawn into the head through the engagement of the blank therewith the jaw 17 moves slightly within the bore 18 until such engagement has become possible. If the jaw 17 were not movable the blanks 27 surface. A gravity feed trough or chute would be forced around the serrations 19 and therefore become marred. The same advantages occur in the disengagement of the jaws 20 with the blanks in that as such jaws are moved to disengage'the Work they tend to rotate the blan {S 27, and through such action the jaw 17 may be oscillated in the opposite direction until such blank has become entirely free. 7

As pointed out in the brief summary of the present invention the beginning of the specification the work-carryin head is adapted to hold in operative position two or more blanks and the threading tool is preliminarily engaged with the blank nearest thereto. During subsequent operations of the ma chine such tool is caused to move into the other blank and cut threads thereon. To provide suitable lubricant for the threading tool which performs its work within the head 9, inasmuch as lubricant supplied to the 6X- terior or front end of the head would be practically ineffective, I have devised the novel mechanism which will now be described. Surrounding the 26, undretained thereon by the outwardlyprojecting ribs 45, is an annular recessed member or ring 16. The inner periphery of tl is ring 46 is recessed at a? and is adapted to provide an oil reservoir therein between rings lt and 26. In Figs. 1 and 3 is illustrated a conduit 48 which mav be connected to any suitable source of lubricant supply, such as the ordinary oil pumps provided on automatic machinery. Provided in the head 9 is a plurality of radial apertures 19 which communicate the inner bore 13 through al gned apertures 49a with the recess 47. The jaw 17 is formed, as indicated at 51. with an oil groove in its outer surface by which the lubricant forced through the holes l9 will be fed to the tapping tool at the interior of the head. The lubricant so introduced to the tapping tool not only serves to lubricate the same in its threading operation, but on account of the force of the oil will serve to eX-trude or carry toward the front of the work-carrying head the metal chips incidental to the threading operation. and in this way eliminate all danger of the jaws becoming clogged.

The work-feeding mechanism The mechanisms for feeding blanks to the worl t-carrying head may of course be varied in details, depending upon the character of the articles to be threaded, the form of such mechanism illustrated the drawings being found acceptable to carry out such desired function in connection with hollow tubular arti les. These articles, as has been indicated, consist of couplings which are to be threaded the entire len th of their ini or is indicated at 50 in Fig. 11 and provides a suitable guide for conveying the blanks one at a time to a position in axial alignment with the center of the work-carrying head. The upper end of this chute maybe connected to any desirable form of hopper by which the blanks are automatically fed thereto. The lower end 51 of the chute isformed to provide a bottom portion against which the lowormost blank rests, and in this position is in such coaxial alignment with the tapping mechanism. Extending from one side of the chute in coaxial alignment with the workcarrying head is a tubular projection 52 which is received in an aperture in the bracket By this construction the chute is supported in proper position and may be adjusted relatively to the face of the work-carrying head by sliding the projection 52 within the bracket Operating longitudinally of the machine and in coaxial alignment with the spindle axis is a feed or push rod which rod is adapted to slidably fit the interior 55 of tubular projection 52 and to have its forward end 56 terminate adjacent the end 51 of the blank chute. Suitable mechanism in the form of a bracket 57 secured to the outer end of rod 54, and also to an operating shaft 58, is provided for actuating such rod in its feeding function. The end 56 at its exterior is provided with a reduced shoulder 59 which is adapted to loosely fit the interior of the cou-.

pling 27 so that as the rod 5i is reciprocated to feed the couplings from the chute to the work-carrying head they are supported in proper alignment. In operation, after the tap has been threaded into the outermost article held in the head 9 the rod 54 is moved throughthe agency of shaft 58, as will appear more fully hereinafter, to the left of 2- until t 1e end 59 is beyond the vertical plane of the chute 50. At this time one coupling 27 drops to the bottom of the chute where it may be engaged by the end 59 as the feed rod is moved in the opposite direction.

The blank feeding mechanism as designed in the present embodiment of my invention is adapted to not only feed the blanks to the work-carrying head, but also to restore the tapping tool to its initial starting point, i. e., with the coupling which has been threaded while in the outer position of the worl-z-carrying head, to be engaged by the rearmost set of blank gripping jaws, these jaws being the pair indicated at the right of Fig. In carrying out the steps enumerated above the end 59 of the rod 54 engages the projecting end of the tap 15 as the blank is fed from the chute to the conduit 9, it of course being obvious that the aws will be at that time retracted through. the actuation of slide 30. its constructed, in the threading operation of the tap, the forward end as it moves to the left of Fig. 5 serves to retract the feeding rod from the coupling being threaded.

through its engagement with the reduced projection 59. This retracted movement of the rod 54 serves, through the connection of the arm'57, to slide the shaft 58 which, as will presently appear, carries thereon a cam 103 adapted to actuate the mechanismfor rotating the cam drum.

The tap holder and blank stripping mecham'sm As has been previously indicated the tap 15 is extended longitudinally of the machine and has its outer or free end detachably engaged by means for holding the same during the threading operation and the blanks as threaded are moved rearwardly along such tap shank toward the free end. At the rear end of the machine, upon guideways 62, provided on the top of bed plate extension 63, is slidably mounted a vertical bracket or. Positioned in a longitudinal opening in the bracket 6t is a spring pressed block 66 having its forward side suitably apertured at 67 in alignment with the end of the tap 15. This aperture 67 and the end of the tap may be provided with any formation of interlocking members, in the form shown the tap having a squared end thereon and the aperture 67 formed accordingly.

Referring to the diagrammatic Figures 12 to 15, inclusive, the sequential steps of the various operating elements are illustrated in the performance of one complete cycle in the operation of the machine. in these figures the block 66 is shown as being connected to the tap 15 at the initial starting point of the threading operation and to remain in such connected relationship until the tap has completed the threading of the foremost article in the work-carrying head 9. At this time the block 66 is retracted toward the outer end of the machine and other mechanisms function to cischarge the blanks which have arrived at the outer end of the tap. While the block is disengaged wita the tap and the stripping mechanism is operating to discharge the blanks from the end of the tap the jaws 20 are retained in engagement with the blanks in the head 9. Subsequent tothis step the jaws are open and a new blank inserted in the head 9 through the reciprocation of rod 54 which, as has been described, serves to move the tap rearwardly of the head 9. This rearward movement of the tap acts to re-engage the outer end thereof with the block 66. During the feeding of the coupling to the work-carrying head the tap is maintained in alignment in the spindle 8 through the engagement of the completed couplings which are held within the bore 14 of such spindle. At the star of the operation of the machine,that is, when first setting up for a new job, there are no couplings within the bore 14 and therefore the outer end of the tap is not supported through the bearing of such couplings with the spindle.

To overcome this feature I have provided in the stripping mechanism spring pressed fingers 69 which project inwardly and serve to engage the tap.

The lingers 69 are, as mentioned, provided at the in s "ipper block Y0 which is centre carried about the rear end of tee tap. The shaft 58 extends from. end to end of the machine and is supported above the bracket "64 in a journal boss '51 secured thereto. Means for supporting the stripper block 70 consists of an arm 72 engaged about the shaft 58 and secured to the bracket (i l by means ofa rod 73.- The shaft 58 is slidably received vithin the journal 7i so that the movement of such shaft willnot affect the position of the bracket 54.

[he cam drum mechanism T he main drive shaft of the machine, which has been designated hereinbefore by the numeral 5., is adapted, through the engagement of tie worm 5 and worm wheel 7, to continnonsly rotate the spindle shaft 8 so-that in the operation of the machine the worlncarrying head 9 is continuously rotated. It is the purpose of the present invention to provide a cam drum or like mechanism which is in tended to actuate, through suitable connections, the blank feeding rod 54:, the blank gripping jaw operating yoke 41 and the tap e gng block 66. This cam drum 10 is pos ined at one side of the bracket L to surround the spindle 8 and has mounted on its outer periphery cam plates 75 and 76 which engage with the cam rolls provided on certain mechanisms connectedto the shaft :58 and to t e brack t 64. In the present disclosed M o-din. nt the cam 10 is rotated intermit lv at the completion of each cycle of op- "ion of the machine, i. e., the same is'held stationary during the threading operation and s effective only during the actuation of the blank feeding and stripping devices.

Referring to Figs. 3 and 7, I haveshown at 7? a sleeve mounted to turn on the spindle 8 within the cam drum 10. This sleeve ha formed its rear end external gear teeth 78 which mesh with a plurality of pinions 79 mounted about pins 80 within the cam drum and engaging with the internal gear teeth 81. The gear teeth may be formed integral with the cam drum 1-0 or of a separate ring member secured thereto. This construction provides for a planetary gear arrangement so that as the sleeve 7? is rotated with the spindle 8 the cam drum 10 will be rotated in the reverse direction and at a much lesser rate of speed. However, as stated hereinbefore, the cam drum 10 is only intended to be rotated one complete revolution during each cycle of operation of the machine and therefore the sleeve 77. is en gaged with the spindle 8 only at such times. The forward end of sleeve 77 is enlarged at '83, and secured to the spindle 8 adjacent the enlarged portion 83 is an annular collar or ring 84. Means in the form of a sliding latch 85, carried in a recess in the sleeve 77, is pro vided to intermittently engage such sleeve vith the collar 84-, andthe-reay cause the mo tation of the drum 10. A vertical bracket or guide block 86 is secured to the rear end of a vertical standard 4 having apertures 87 and 88 therein to receive the shaft 58 and the collar respectively, Formed in the rear face of the guide block 86 are vertical guideways 88", in which is mounted for vertical reciprocation a cam latch member 89 having its lower end provided with means adapted to cooperate with the latch to retain said latter member 1n retracted position, i. e.,

out of engagement with the collar 84, A.

compression spring 90, received in a longitudinal aperture 91 formed in the sleeve 77 in alignment with the recess 92, is provided to engage the rear end of latch 85 to keep such member normally pressed toward the collar 84. The outerperiphery of thereularged portion 83 of sleeve 77 i-sformedwith an encircling groove 93, in which the lower end of the vertical latch 89 is adapted to be received. The groove 98 communicates with the recess 92 to permit the latch 89 to engage with a recess 94: formed in the outer side of the latch 8. It will be apparent fromthe foregoing that while the lower end 9.5 of latch 89 is engaged with the recess 94; the cam drum will not rotate, and that upon freeing the end '95 from engagement with the latch 85 the latter member will be engaged. through the action of spring 90, with the collar 84 secured to the spindle 8 and consequently the drum will be rotated.

In carrying out the function of the various i elements controlled through the cams mounted on the cam drum 10 it is only necessary to rotate such drum one complete revolution, and therefore the latches 85 and 95 have been so designed that they operate automatically to disengage the drum with the driving spindle 8 at each complete rotation of the drum. In Fig. 6 thelatch member 85 is shown in retracted position. Assuming now that the latch 89 is lifted to permitv latch 85 to en- 7' gage the drum with the spindle .8 the sleeve 77 will be caused to rotate in the direction Of the arrow indicated in such figure. In

as being formed with an inclined cam face 96 Ii -fil ingoperation. This rockshaft 98 is actuated that the same will ride in the groove 93 in position ready to disengage the latch 85 as that member is carried by the sleeve 7 7 in its rotation, as has been described.

The operating shaft 58 The shaft 58, which extends from end to end of the machine and is slidably mounted in brackets 3, 4 and 71, carries thereon the arm 57 which actuates the feeding rod 54, the arm 72 connected to the stripping mech anism, spaced adjustable collarsadapted to engage the jaw operating yoke 41, a cam the shaft 58 and at the time the threading operation has been completed the cam 103 has been moved to engage with an arm 104 secured to the rockshaft 98. Through this engagement the rockshaft is rotated and the latch 89 raised to permit the connection of the cam drum to the driving spindle. A complete description has been given hereinbefore of the sequential steps in the operation of the blank feeding rod, the blank gripping jaws in the work-carrying head, the tap holder and the stripping mechanism, all of which devices are controlled through the reciprocation of shaft 58 after the cam drum is set in motion. The first function of the cam drum in its rotation is to retract the block 66 to the left of Fig. 1 to disengage the same with the end of the tap, suitable mechanism being provided in the form of a link 106 secured at one end by a pin 107 to the sliding standard 64 and at its other end to the outer end of a pivoted arm 108. The arm 108 is mounted about a stud 109 on the bed plate of the machine, and carries at its outer end a cam roll 110 in line with the cams and 76 on the drum 10. The shaft 58 is slidable within the ournal 71, which latter member is secured to the head 66, and as the head 66 is actuated by the cam 7 5 the shaft 58 remains stationary. Subsequent to the disengagement of the tap holder with the tap 15 the cams on drum 10 engage the roll 102 and effect the reciprocation of shaft 58. The first part of the movement of shaft 58 causes one of the collars 111 to contact with the projection 43 on the yoke 41 and thus move the slide 30 to the left to Fig. 5 to disengage the jaws 20 with the blanks carried in the head 9. Further movement of the shaft 58 places the end 59 of the rod 54 in position to feed a fresh blank. At this time the cams on the drum 10 cause the shaft 58 to move to the right of Fig. 2 and thus carry the blank held in the lowermost position of chute 50 to the work-carrying head 9. This movement, as has been described, not only carried out the feeding function, but also retracts the tap in the, initial starting position and engages the outer end thereof with the holding block 66. Immediately after the tap has been restored to starting position another of the collars 111 actuates the yoke 41 to close the work-gripping aws 20 on the blanks in the head 9. At this time the cam drum has made one complete revolution and the inclined surface 96 has withdrawn the latch from engagement with the collar 84 and the drum ceases to rotate.

It will be apparent from the foregoing that I have accomplished the objects primarily stated and that I have provided a new and improved machine which continuously and automatically threads couplings or like articles, one at a time, as they are fed to the machine. Each of the several operating elements in the construction of the present disclosed embodiment are adjustable one to the other, so that the machine may be regulated to adapt the same for operation on articles of varying sizes or lengths of thread to be cut. While in such embodiment the work is held in a rotating holder and the threading tool is mounted stationary, this invention contemplates the construction of a machine wherein the work holder is non-rotatably mounted and the driving mechanism is detachably secured to the tap so that such latter member may be rotated relatively to the work.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the means and the steps herein disclosed, provided those stated by any of the following claims or their equivalent be employed.

' I therefore particularly point out and distinctly claim as my invention 1. In a method of threading hollow articles, the steps which consist in intermittently feeding such articles to the first of two sets of aligned gripping jaws, axially moving a tap into the gripped article to cut threads on the interior thereof, and moving said tap and threaded article to a position for engagement by the second set of gripping jaws, said last step being performed simultaneously with the feeding operation.

2. In a method of threading hollow articles, the steps which consist in threading a tap into one of such articles, gripping such threaded article whereby further relative rotation of the tap and said article will cause longitudinal movement of the tap, feeding a second article into axial alignment with said first-named article, gripping such see ond article and threading the same upon said relative rotation between said first article and the tap.

3. In a method of threading hollow articles, the steps which consist in intermittently feeding such articles to the first of two sets of aligned gripping jaws, axially movzng a tap into the gripped article to cut threads on the interior thereof, supporting the rear end of the tap during the threading operation, and moving said tap and threaded article to a position to be gripped by the second of gripping jaws, said last step being performed simultaneously with the feeding operation.

4. In a method of threading hollow articles, the steps which consist in intermittently feedin such articles to the first of two sets of aligned gripping jaws, axially moving a tap into the gripped article to. cut threads on the interior thereof, supporting the rear end of the tap during he threading operation, moting said tap and threaded article to position to be gripped by the sec ond set of gripping jaws, and rel asing said gripping jaws during said feeding operatron.

5. In a. method of threading hollow articles, the steps which consist in movin a tap through'said articles, intermittentl feeding one article at a time to the first of two sets of aligned gripping aws, threading said tap partially through said gripped article, and moving said tap with said partially threaded article to a'position for engagement by said second set of jaws, said last step being performed simultaneously with said feeding operation. I

6. In a method of threading hollow ar ticles, the steps which consist in presenting blanks in coaxial alignment with a straight tap, gripping two of said blanks in alignment, passing the tap entirely through one and partially through the other of said gripped blanks, releasing the gripping mechanism, retracting said tap and partially threaded blank to discharge the threaded blank through said gripping m chanism, and feeding an unthreaded blank to said gripping mechanism simultaneously with said last-named step.

7 In a method of threading hollow articles, the steps which consist in holding two such articles in alignment with a threading tool, one of said articles being threaded and having engagement with the thread cutting portion of said tool, and in revolving the sat holding means to feed said tool through the threaded article and to cut threads on the interior of said other article.

8. Threading mechanism comprising a work-carrying head, two sets of axially aligned gripping jaws mounted therein, a

tap movable axially of said jaws, means for intermittently feeding blanks to one set of jaws, and means for rotating said head, said tap serving as a means to transfer work from said one set of jaws to the other.

9. Threading mechanism comprising a worlccarrying head, two sets of gripping jaws mounted therein, a tap movable axially of said jaws, means for feeding blanks to one set of said jaws, means for rotating said head to thread the tap into such engaged blank, and means for retracting said tap together with the blank threaded thereon in position for engagement with the other set of said jaws.

. 10. In a machine of the character described, the combination of a hollow spindle, a tap having threaded elements at one end, said tap being located interiorly of said spindle and unsupported thereby, a work-carrier mounted on said spindle, disengageable workgripping mechanism carried thereby, means for detachably engaging the shank end of said tap, and means for relatively revolving said carrier and tap.

11. In a machine of the character described, the combination of a hollow rotatable spindle, a tap having threading elements at one end, said tap being located interiorly of said spindie and unsupported thereby, a work-carrier mounted on said spindle, disengageable workgripping aws carried thereby, means for intermittently feeding blanks to said jaws, and detachable means for engaging the shank end of said tap.

l2. Ina machine of the character described,

the combination of a hollow spindle, a workcarrying. head mounted thereon, gripping jaws carried by said head, means for opening and closing said jaws, a tap having thread. ing elements at one end, said tap being lo cated interiorly of said spindle andunsupported thereby, means for intermittently feeding blanks to said head, means for detachably engaging the shank end of said tap, and means for relatively revolving said carrier and tap. i

13. In a machine of the character described, the combination'of a drive shaft, a hollow spindle, means for rotating said spindle from said shaft, a work-carrying head mounted on sa1d spindle, grippmg aws carried by said head, means for opening and closin said j aws,'a tap having threading elements one end, said tap being located interiorly of sair spindle and unsupported thereby, means for intermittently feeding blanks to said head, and means actuated from said drive shaft for effecting the operation of said gripping jaws and said feeding means.

14. In a machine of the character described, the combination-of a drive shaft, a hollow spindle, means connecting said spindle to said shaft for revolving the former, a work carrying head mounted at one end of said Cal spindle, a plurality of sets: of gripping jaws carried by said head, an axially aligned tap adapted to co-operate with said head to thread blanks carried by the latter, means for intermittently feeding blanks to one of said sets of jaws, and means operated by said fee lin means adapted to open said jaws to release the blanks engaged thereby, said tap serving as a means to transfer blanks from said one set of jaws to another.

15. Threading mechanism comprising a work-carrying head. outer and inner sets of aligned mounted therein, means ft '2 iitly feeding blanks totho axially aligned tap "he gripped blanks, and

adapted to t means for trans the blank from the err outer set of aws to the other set of aws.

16. Threading mechanism comprising a work-carrying head, outer and inner sets of aligned gripping jaws mounted therein, means for intermittently feeding blanks to the out-er set of said an axially aligned tap adapted to thread tie gripped blanks, and means including the feeding ieans for transferring the blank from the outer set of jaws to tne other set of jaws.

17. Threading mechanism comprising a work-carrying head, outer and inner sets of aligned gripping jaws mounted therein, means for intermit ently feeding blanks to the outer set of said aws, an axially aligned tap adapted to thread the gripped blanks, and means including the feeding means and said tap for transf rring the blank from the outer set of aws to the other set of aws.

l8. Threading mechanism comprising a work-carr ing head, outer and inner sets of ali ned gripping jaws mounted therein, means for intermittently feeding lanks to the outer set of said jaws, an axially aligned tap located interiorly of said head and unsupported thereby, said head and tap being c 1. though the blank gripped in said outer set aws, and means for transferring said tap d blank threaded thereon into position for engagement said other set of jaws.

9. Threading mechanism comprising a workarrying head, outer and inner sets of l 'ned gripping jaws mounted therein, means for intermittently feeding blanks to the outer set of said jaws, an axially aligned "ated to thread the latter only partially tap located imeriorl of said head and unsupported thereby, said head and tap being actuated to thread the latter only partially through the blank gripped in said outer set of jaws, and means for transferring said tap and blank threaded thereon into position for en agement by said other set of jaws, said last named means being actuated in timed relation with said feeding means. 7

20. Threading mechanism comprising a rotatable work-carrying head, a plurality of sets of gripping jaws mounted therein, means for opening and closing said jaws, a tap located interiorly of said head and unsupported thereby, means for intermittently feeding blanks to one of said sets of jaws, and means connected to said feeding means adapted to actuate said jaw opening and closing means, said tap serving as a means to transfer blanks from said set of jaws to another.

21. In a tapping machine, a tap, mechanisms for longitudinally shifting the tap in two directions, means for gripping the work to be threaded by the tap, and means auto matically operated by an advancing movement of the tap for initiating the actuation of said mechanisms.

22. In a tapping machine, a tap, mechanisms for longitudinally shifting the tap in two directions, means for gripping the work to be threaded by the tap, one of said mechanisms serving to operate the work gripping means and means automatically operated by an advancing movement of the tap for initiating the actuation of said mechanisms.

23. In a tapping machine, a tap, mechanisms for longitudinally shifting the tap in two directions, means for gripping the work to be threaded by the tap and means operated by one of said mechanisms for operating the gripping means.

24. In a metal cutting machine the combination of a cutting tool, means for holding work to be operated upon by said tool, means for elfecting relative rotation between the work holding means and said tool, a camming mechanism COELXlflllY. arranged relative to said means for effecting a relative longitudinal movement between the work and tool and means for intermittently operatively connecting said rotation means to the camming mechanism.

25. In a metal cutting machine the combination of a cutting tool, means for holding work to be operated upon by said tool, means for efiecting relative rotation between the work holding means and said tool, a camming mechanism coaxially arranged relative to said means for effecting a relative longitudinal movement between the work and tool, a clutch mechanism for connecting the camming mechanism to the rotation means, and means for operating the clutch mechanism and controlled by said relative longitudinal movement effected between the work and tool.

26. In a metal cutting machine the combination of a cutting tool, means for holding work to be operated upon by said tool, means for effecting relative rotation between the work holding means and said tool,a camming mechanism coaxially arranged relative to said means for efiecting a relative longitudinal movement between the work and tool and a clutch mechanism intermittently opperated by the camming mechanism.

27. In a metal cutting machine the combination of a cutting tool, means for holding work to be operated upon by said tool, means for efiecting relative rotation between the work holding means and said tool, a camming mechanism coaxially arranged relative to said means for effecting a relat ve longitudinal movement between the work and tool, means for intermittently operatively connecting said rotation means to the camming mecl: anism, said last named means controlled by said relative movement between the work and tool.

28. In a metal cutting machine the combi nation of a cutting tool, means for holding work to be operated upon by said tool, means for effecting relative rotation between the work holding means and said tool, a camming mechanism coaxially arranged relative to said means for effecting a relative longitudinal movement between the work and tool, means for intermittently operatively. connecting said rotation means to the camming mechanism and means for automatically removing work from the work holding means.

29. In a metal cutting machine the combination of a cutting tool, means for holding work to be operated upon by said tool, means for effecting relative rotation between the wor: holding means and said tool, a camming mechanism coaxially arranged relative to said means for effecting a relative longitudinal movement between the work and tool, a clutch mechanism for connecting the camming mechanism to the rotation means, means for operating the clutch mechanism and controlled by said relative longitudinal movement effected between the work and tool, and means for automatically removing the work from the work holding means.

30. In a metal cutting machine the com ination or" cutting tool, means for holding work to be operated upon by said tool, means for effecting relative rotation between the work holding means and said tool, a camming mechanism coaxially arranged relative to said means for effecting a relative longitudinal movement between the work and tool, a clutch mechanism for connecting the camming mechanism to the rotation means, means for operating the clutch mechanism and controlled by said relative longitudinal movement effected between the work and tool, means for automatically removing work from the work holding means and other means for automatically feeding new work to the tool.

31. In a metal cutting machine the combination 01 a cutting tool, means for holding work to be operated upon by said tool, means for effecting relative rotation between the work holding means and said tool, a camming mechanism coaxially arranged relative to said means for effecting a relative longitudinal movement between the work and tool, a clutch mechanism for connecting the camming mechanism to the rotation means and means for operating the clutch mechanism and controlled by said relative longitudinal movement etlected between the work and tool.

32. The method of forming internal threads in hollow articles, comprising holding an internally threaded article and a hollow blank in axial alignment, and presenting such alignsf *ticles to a thread cutting tool in such ma r that the tool acts on the blank while the already hreaded article by engaging thread cutting portions of the tool forms a lead screw therefor.

The method of tapping hollow articles, which consists in holding two of such articles in coaxial alignment with a tap so that the tap passes through two articles successively, utilizing the p nrso threaded article as a lead screw for tapping the second article, and thereafter causing the first threaded article to pass onto the shank of the tap and gripping the second article as a lead screw and an aligned third article as a blank to be threaded.

34:. A threading mechanism comprising a work-carrying head, gripping jaws mounted therein, means for opening and closing the jaws, a tap located coaxially of'the head, means for causing relative rotation between the head and tap, means for intermittently feeding blanks to said jaws, and means for connecting with said feeding means adapted to actuate said jaw opening and closing means.

35. The method of forming threads on articles, comprising holding a previously threaded article and a blank in alignment, and presenting such aligned articles to a threadcutting tool in uch manner that the tool acts 7 on the second article, while the first article forms a lead screw for the tool.

36. Threading mechanism comprising a work-carrying head, two sets of axially aligned gripping jaws mounted therein, a

tap movable axially of said jaws, the head.

and tap cooperating, and there being means for rotating one of them, and means for inter-J mittently feeding lanks to the outer set of jaws.

3?. hreading mechanism comprising a work-carr ing head, two sets of gripping jaws mounted therein, a tap movable axially of said jaws, 1 cans for feeding lanks to one set of said jaws, means for causing a relative rotation between said head and tap to thread the tap into such engaged blank, and means for retracting said tap together with the blank threaded thereon in position for engagement with the other set of said aws.

38. Threading mechanism comprising a work-carrying head, two sets of aligned gripping jaws mounted therein, means for intermittently feeding blanks to the outer set of said jaws, a tap axially aligned with the ihead, and-one of them being rotated to thread the tap partially through the blank gripped in saidouter set of jaws, and means for trans ferring said tap and blank threaded thereon into position for engagement by said other set of jaws.

39. Threading mechanism comprising a work-carrying head, two sets of aligned gripping jaws mounted therein, means for intermittently feeding blanks to the outer set of i said jaws, a tap axially aligned with the head,

and one of them being rotated to thread the tap partially through the blank gripped in said outer set ofjaws, and means for transferring said and blank threaded thereon into position for engagement by said other set of jaws, said last named means being actuated in timed relation with said feeding means.

Signed by me, this 22nd day of June, 1927.

JAMES F. PATTON. 

